Node.js Commands

Introduction to Node.js Commands

Node.js is cross-platform, fast and lean JavaScript runtime environment built on JavaScript engine. Node.js uses an event-driven, non-blocking I/O by which we can achieve low latency and high throughput and makes it lightweight and efficient. Node.js will be useful for both servers and desktop applications. Node.js is written in C/C++, JavaScript and its package ecosystem NPM (node package manager), consists of a large number of open source libraries in the package. Node.js was introduced in 2009 by Ryan Dahl for Linux and Mac OS and now runs on different platforms like Windows, UNIX, Linux, Mac OS X etc. It uses JavaScript on the server.

Basic Node.js Commands

1. Program to display hello world using Node.js?

We can write a program in node.js to print hello world as below.
We need to create a file named “hello.js” and write the below code

5. How to read the query string in node.js?

In order to read the query string in node.js, we need to implement as below code where create-server() function has a request parameter/argument which represents an argument from a client as an object. Sample code as below:

Intermediate Node.js Commands

1. How to trigger a report on the fatal error in node.js?

The above node.js command enables the report on the fatal error and terminates the application and useful to inspect various diagnostics.

2. What is the use of a console class in node.js and how to use it?

Console class in node.js is used as a debugging console similar to in JavaScript and console class in node.js has three methods console.log(), console.error() and console.warn() are used to write to any node.js streams.

4. How to certificate class in node.js with an example?

We can use certificate class in node.js with help of crypto module in node.js as it provides certificate class and with which we can able to work with SPKAC data and mostly used for handling output from HTML5 <keygen> element.

15. How to create a new instance of a certificate class in node.js?

The new instance of a certificate class can be created using new keyword in node.js as below:

2. Explain Asynchronous and Synchronous calls in node.js?

In node.js, EventEmitter calls all listeners synchronously in which order they registered as it is important to maintain proper sequence to avoid race conditions and listener functions can switch to an asynchronous mode of operation using methods such as setImmediate() or process.nextTick()

Tips And Tricks to use Node.js Commands

Always have a check for errors – never throw any errors and miss to catch the errors.

Good to know about npm – you can know by installing modules with –S and –D options.

Use exact versions only in package.json –By default npm adds caret when option –S is used and we need to manually edit to use exact versions and with open source modules we can use directly.

Conclusion – Node.js Commands

Finally, it’s a conclusion about different types of node.js commands and some tips and tricks to use them. I hope you will have a good understanding of node.js commands and how to use them after reading this article.

Recommended Articles

This has been a guide to Node.js Commands. Here we have discussed basic, immediate as well as advanced Node.js Commands. You may also look at the following article to learn more-